1. Field of the Invention
The invention relates to a method and a device for connecting subscribers in several telecommunication networks under one dial number.
Telecommunication is currently executed, on one hand, over wired telecommunication networks, also referred to as wireline networks, and, on the other hand via wireless telecommunication networks, so-called mobile radio communication networks.
It would be desirable that a subscriber can be reached under one dial number independent of the networks the subscriber uses for making the call. Although modern telecommunication networks enable rerouting of telephone calls, i.e., calls for the subscriber which may be received, for example, via the mobile radio communication networks, can be rerouted to a predetermined number of a wireline network, this type of call rerouting, however, does not mean that the subscriber can be actually reached under a single dial number.
As a disadvantage, the subscriber has to establish call rerouting each time when needed and cancel the same when not needed. In addition, for rerouting the call, the actual dial number, to which the call is to be rerouted, has to be entered. If the subscriber changes his location or desires rerouting of the call to a different dial number, then this dial number has to be entered each time anew.
2. Description of the Related Art
In the article by Jones, D. R.: “AIN Network Capabilities for Wireless/Wireline Integration” in: Annual Review of Communications, Vol. 50, 1997, pp. 923–930, there is described a method for connecting subscribers in several telecommunication networks, wherein a dial number is assigned to the subscriber, under which number the subscriber can be reached. One of the telecommunication networks can be a mobile radio communication network and another telecommunication network can be a digital intelligent wireline network. A so-called follow-me-service is established. However, the wireline network is not expanded to include mobility functions. The follow-me-function is implemented by network-external devices, and the described functions correspond to conventional call transfer functions between several dial numbers in the participating communication networks.
A similar approach is described in the article by Kolipakam, M. V. et al.: “Personal Communications Services using the Intelligent Network” in Intelligent Networks, The Path to Global Networking, Proceedings of the International Council for Computer Communications, Intelligent Networks Conference, Tampa, May 4–6, 1992, pp. 384–390. In this case, too, no actual integration of the wireline network into the mobility management of the mobile radio communication network is provided.
EP-A-0 738 093 relates to a communication system, wherein a subscriber can be reached under a single personal dial number. However, the old network structures are preserved, meaning that a subscriber relationship with a respective specific network-internal dial number is established for each connected communication network. This described method has no impact on existing communication networks and, more particularly, does not implement a genuine mobility management based on a uniform database.